The object of the present invention is an electromechanical escapement device and a timepiece part utilizing such a device.
For a mechanical timepiece part, the escapement device is used for sustaining the oscillation movement of the mechanical oscillator comprising the balance and the balance spring on the one hand and for transmitting the frequency of this oscillator to the gear-train driving the time display.
Entirely mechanical escapement devices are therefore well-known in the prior art. The manuals “Echappements et moteurs pas à pas” (Escapements and step motors) of Charles Huguenin edited by the Fédération des Ecoles Techniques de Suisse (Swiss Federation of Technical Colleges) and “Théorie d'horlogerie” (Watch-making theory), ISBN 2-940025-10-X, also edited by the Fédération des Ecoles Techniques de Suisse, describe several mechanical escapement devices called <<anchor>>, <<detent>>, <<Graham>> escapements, etc.
As mentioned earlier, traditional mechanical escapement devices directly transmit the frequency of the mechanical oscillator to the gear-train driving the time display. The frequency of the mechanical oscillator, generally comprised between 2 and 4 Hz, is unfortunately not very accurate and further highly dependent on the position of the watch. The accuracy of a mechanical watch is consequently less than that of an electronic quartz watch.